All tools
5,982 free tools, organised into 9 categories — everything runs in your browser, nothing is uploaded. Pick a topic below, or search from the homepage.
Calculators & Converters 2,286 tools
Free online calculators and unit converters for finance, health, math, science, home improvement and everyday questions. Every calculator runs entirely in your browser — instant results, no signup, nothing sent to a server.
- Business & Marketing (51)
- Tax & Wages (26)
- Medical & Clinical (61)
- Health & Fitness (125)
- Chemistry (54)
- Physics (41)
- Electronics (71)
- Automotive (42)
- Music & Audio (46)
- Gaming (53)
- School & Study (60)
- Crypto & DeFi (34)
- Compliance & Policy (12)
- City Costs & Commuting (8)
- Social Media & Creator (1)
- Astronomy (23)
- Geography & GPS (14)
- Statistics & Probability (23)
- Geometry (43)
- Math & Algebra (170)
- Food, Cooking & Brewing (33)
- Farming & Garden (53)
- Home & DIY (132)
- Finance & Money (153)
- Conversions & Units (254)
- Date & Time (77)
- Photo & Video (41)
- Sports & Recreation (82)
- Clinical Scores & Lab (68)
- Machining & Manufacturing (42)
- Electrical & NEC (32)
- Shipping, Freight & Trade (39)
- Sustainability & ESG (42)
- Legal & Regulatory (42)
- Exams & Admissions (40)
- More Calculators (198)
Developer Tools 1,599 tools
Fast, private developer utilities — JSON, encoding, hashing, color, CSS, generators, formatters and reference cheatsheets. Everything runs client-side in your browser, so your code and data never leave your device.
Text & Writing Tools 890 tools
Text tools for writers, students and social media — case converters, font and Unicode generators, counters, cleaners, ciphers and encoders. All processing happens in your browser; your text is never uploaded.
Image & PDF Tools 163 tools
Edit, convert and generate images and PDFs right in your browser. Resize, compress, convert formats, build PDFs, extract colors and more — your files never leave your device, so it's completely private.
Everyday & Quick-Help Apps 123 tools
Handy little browser apps — generators, trackers, planners, timers and references that solve an everyday problem in seconds. Free, private, and instant, with nothing to install.
AI Tools 862 tools
Free, private AI utilities — prompt builders and testers, token & cost calculators, model comparisons, output cleaners, RAG and developer helpers, and image-generation prompt builders. Everything runs in your browser; bring your own API key for live model calls.
- Token & Cost Calculators (154)
- Prompt Builders & Testers (210)
- Image, Video & Audio Generation (32)
- RAG, Agents & Fine-Tuning (32)
- Output Cleaning & Evaluation (82)
- Governance, Safety & Compliance (83)
- Business & Workflow Builders (62)
- Content Generators & Writing (22)
- AI Glossary & Comparisons (41)
- More AI Tools (144)
Learn AI 2 tools
Learn AI from zero — clear explainers, a full glossary, step-by-step tutorials, roadmaps, model comparisons and interactive quizzes covering LLMs, prompting, RAG, fine-tuning, agents and more. Free, no signup.
Validators & Checkers 7 tools
Free, private validators and format checkers — VAT and tax IDs, IBAN and bank codes, national identity numbers, VIN, accessibility (WCAG), data formats and more. Every check runs entirely in your browser; nothing you enter is uploaded or stored.
Tax & Payroll 50 tools
Free tax, payroll and take-home calculators by country and region — income tax, VAT/GST, payroll and social contributions, severance and statutory pay. Real published rates, computed instantly in your browser, nothing uploaded.